Yes. The entire core application — including the sky map with 100M+ stars, plate solver, sequencer, and all device control — works without an internet connection. Star catalogs are embedded in the app. The only features that require internet are optional: HiPS sky survey tiles download, astrometry.net index downloads, and Pro cloud services.

No. OpenSkyLab runs locally on your machine with zero accounts, zero telemetry (unless you opt in), and zero cloud dependencies. You download it, run it, and start imaging. An account is only needed if you choose to purchase Pro plugins.

Any device compatible with INDI (Linux/macOS — 200+ drivers) or ASCOM Alpaca (Windows). This includes mounts, cameras (CCD/CMOS), DSLR/mirrorless (Canon CR2/CR3, Sony ARW, Nikon NEF), focusers, filter wheels, rotators, domes, weather stations, and flat panels from all major manufacturers: ZWO, QHY, Celestron, Sky-Watcher, iOptron, Pegasus, and more.

OpenSkyLab provides a modern, web-based UI built with React and Three.js instead of Qt widgets. It runs as a lightweight Tauri app (10x smaller than Electron), supports both INDI and ASCOM from the same interface, and offers features KStars doesn't have: live stacking, framing assistant, advanced sequencer with conditions/triggers, and Pro plugins with AI/ML capabilities. The core is MIT licensed (vs KStars' GPL).

OpenSkyLab is cross-platform (Linux + Windows + macOS coming), while NINA is Windows-only. OpenSkyLab includes a full interactive sky map, native INDI support, and its Pro plugins offer unique capabilities like ML frame scoring and AI night planning that NINA doesn't have. Both have plugin systems, but OpenSkyLab's is built on Rust for performance and safety.

Yes, in two ways. The free core lets you access the web UI from any device on your local network — just point a browser to your rig's IP. For remote access outside your network (without port forwarding), the Relay plugin creates a secure WSS tunnel through our cloud relay server. Relay is included in both OpenSkyLab Plus and the one-time PRO Lifetime license — no subscription is required just to use it.

ASTAP (offline, ~3-5 seconds per solve) is the primary solver. Astrometry.net local indexes are also supported as a fallback. You can download solver index databases directly from the Settings panel. No internet connection is required for plate solving.

No — and you're not even required to subscribe for Pro. The free core is a complete, feature-rich imaging platform with full parity to KStars and NINA. Pro plugins (AI planning, ML scoring, analytics, image processing, and more) are 100% optional, and you can unlock them either way: subscribe to OpenSkyLab Plus (all 9 Pro plugins + Cloud in one plan) or buy PRO Lifetime once for a flat fee and never pay again. The only piece that's subscription-only is OpenSkyLab Cloud, because it runs on our servers and has an ongoing cost — everything that runs locally on your machine can be a one-time purchase.

Yes. The osl-plugin-sdk crate is MIT licensed and provides a Rust trait + macro system for building custom plugins. You can create new device adapters, analysis panels, or automation tools. Your plugins can have their own UI panels that load dynamically in the app.

OpenSkyLab integrates with PHD2 via its JSON-RPC protocol. You get real-time RMS stats, guiding charts, dither control, and state monitoring — all from within the OpenSkyLab interface. PHD2 runs as a separate process and OpenSkyLab connects to it automatically.